Tissue fixation

ABSTRACT

Methods and systems are provided for tissue stabilization. Some aspects include a carrier member having a length, width, and thickness, wherein the length and width are each at least two times greater than the thickness; attachment members extending from the carrier member and that engage connective tissue; and stabilizing members, each of which can couple a respective attachment member to the carrier member and is substantially positionally fixed relative to the carrier member.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a divisional of U.S. patent application Ser. No. 12/783,507, filed May 19, 2010, the disclosure of which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

The present invention generally relates to tissue stabilization.

BACKGROUND

Lacerated flexor tendon repair is a procedure performed approximately 145,000 times a year in the United States alone. Early post operative mobilization is beneficial to restoring maximal tendon function following injury and repair. Adhesion formation is a common complication following tendon repair, but can be reduced through motion rehabilitation programs. By preventing adhesion formation and gliding resistance, tendon healing may be enhanced. However, the failure rate of tendon repairs is close to 30 percent, primarily because of overloading at the repair site. Although an objective of tendon repair is to provide adequate strength for passive and active motion during rehabilitation, it is important to maintain a delicate balance between rehabilitative motion protocols and fatiguing the repair site.

A procedure for lacerated tendon repair is to use suture to mend the two ends of a tendon together using complex suture patterns. While this provides a good initial repair, the strength and quality of the repair may quickly degrade with subsequent loading and mobilization. Although postoperative therapy may be utilized to reduce adhesion, the resulting tension can induce gap formation or tendon rupture at the repair site, seriously impairing the outcome of the repair. Gapping at the repair site has many negative effects, such as reduced repair strength, tendon rupture, and an increased probability for adhesion.

BRIEF SUMMARY OF THE INVENTION

According to various embodiments of the subject disclosure, an apparatus for fixating connective tissue is provided. The apparatus may comprise a carrier member having a first part, a second part, and a junction therebetween. The carrier member may be configured to encompass, at least in part, an interior space. The apparatus may also comprise one or more first attachment members protruding into the interior space and at a first angle from the first part toward the junction. The one or more first attachment members may be configured to engage a first portion of connective tissue in the interior space for attaching the first part to the first portion. The apparatus may comprise one or more second attachment members protruding from the second part into the interior space. The one or more second attachment members may be configured to engage a second portion of connective tissue in the interior space for attaching the second part to the second portion. In some embodiments, when the first part is attached to the first portion and the second part is attached to the second portion, the first portion and the second portion are limited in being pulled apart from one another during physiological use of the connective tissue.

In some embodiments, the carrier member has a length, width, and thickness. The length and width may each be at least two times, three times, four times, five times, eight times, ten times, 15 times, 20 times, 25 times, 50 times, 100 times, or 200 times greater than the thickness.

In some embodiments, the one or more second attachment members protrude at a second angle from the second part toward the junction. In some embodiments, at least one of the first angle and the second angle is less than or equal to about 5 degrees, 10 degrees, 15 degrees, 20 degrees, 30 degrees, 40 degrees, 45 degrees, 50 degrees, 65 degrees, 75 degrees, or 85 degrees. The first angle and the second angle are of about the same magnitude.

In certain embodiments, an average thickness of at least one of the one or more first attachment members is such that when the first part is attached to the first portion, the first angle is maintained at less than about 5 degrees, 10 degrees, 15 degrees, 20 degrees, 30 degrees, 40 degrees, 45 degrees, 50 degrees, 65 degrees, 75 degrees, 85 degrees, or 90 degrees during physiological use of the connective tissue. The average thickness may be measured along a direction substantially parallel to a longitudinal dimension of the carrier member.

In some embodiments, at least one of the one or more first attachment members comprises at least one of a hook, a barb, and a pin. In some embodiments, at least one of the one or more first attachment members is less elastic than is the carrier member.

In certain embodiments, an average height of at least one of the one or more first attachment members is greater than about 6 millimeters, between about 6 and 4 millimeters, between about 4 millimeters and 2 millimeters, between about 2 millimeters and 1.75 millimeters, between about 1.75 millimeters and 1.50 millimeters, between about 1.50 millimeters and about 1.25 millimeters, between about 1.25 millimeters and about 1 millimeter, between about 1 millimeter and about 0.75 millimeter, between about 0.75 millimeter and about 0.5 millimeter, between about 0.5 millimeter and about 0.25 millimeter, between about 0.25 millimeter and about 0.10 millimeter, between about 0.10 millimeter and about 0.075 millimeter, between about 0.075 millimeter and about 0.05 millimeter, between about 0.05 millimeter and about 0.025 millimeter, between about 0.025 millimeter and about 0.01 millimeter, or less than about 0.01 millimeter.

In some embodiments, the first part comprises a tissue-facing surface that faces the connective tissue when the first part engages the first portion. The first part and each of the one or more first attachment members may meet at a respective base having an area. A ratio of the total area of all the bases to the total area of the tissue-facing surface may be greater than or equal to about 0.05, 0.10, 0.20, 0.30, 0.40, 0.50, 0.60, 0.70, 0.80, 0.90, or 0.95.

In certain embodiments, a ratio of a greatest width of a base of a first attachment member to an average height of the first attachment member is greater than or equal to about 1.4, between about 1.4 and 1.2, between about 1.2 and 1.0, between about 1.0 and 0.95, between about 0.95 and about 0.90, between about 0.90 and about 0.80, between about 0.80 and about 0.70, between about 0.70 and about 0.60, between about 0.60 and about 0.50, between about 0.50 and about 0.40, between about 0.40 and about 0.30, between about 0.30 and about 0.20, between about 0.20 and about 0.10, or less than or equal to about 0.05. The greatest width may be measured along a direction substantially perpendicular to a longitudinal dimension of the base and substantially parallel to the tissue-facing surface. The longitudinal dimension of the base may be a direction the first attachment member is protruding toward in substantially the same plane as the base.

In some embodiments, at least three of the one or more first attachment members are arranged with respect to the carrier member in at least one of a grid-like array and a staggered array. In some embodiments, at least one of the first attachment members comprises a polymer. In some embodiments, at least one of the first attachment members comprises non-polymeric resorbable biomaterials including calcium-based ceramics (e.g., calcium phosphates, various hydroxyapatites, carbonates or sulfates), biocompatible silicates (e.g., bioglasses), silicon or titanium nitrides or oxides, or their composites with degradable polymers (e.g., biomedical grade degradable or non-degradable polyester or polyurethane). In some embodiments, at least one of the one or more first attachment members comprise at least one of a thermoplastic, ultraviolet curable resin, biodegradable polyester, polycarbonate urethane, and polyurethane (e.g., programmed degradable polyurethane). These materials may be medical grade. The biodegradable polyester may comprise at least one of polycaprolactone, poly(L-lactide), poly(D,L-lactide), and poly(glycolide-co-lactide). The molecular weight of the polycaprolactone may be between about 150,000 and 250,000 and the molecular weight of the poly(L-lactide), poly(D,L-lactide), or poly(glycolide-co-lactide) is between about 150,000 and 250,000. In some embodiments, the molecular weight of the polycaprolactone may be less than about 150,000 and the molecular weight of the poly(L-lactide), poly(D,L-lactide), or poly(glycolide-co-lactide) may be less than about 150,000. In some embodiments, the molecular weight of the polycaprolactone may be greater than about 250,000 and the molecular weight of the poly(L-lactide), poly(D,L-lactide), or poly(glycolide-co-lactide) may be greater than about 250,000.

In some embodiments, the carrier member comprises an elastomer (e.g., medical grade). In some embodiments, the carrier member comprises at least one of an ultraviolet curable resin, methacrylated polybutadiene, polyester urethane, polycarbonate polyurethane, polyether urethane, silicone rubber, nitrile rubber, polyphosphazene, and acrylic copolymer. These materials may be medical grade. In some embodiments, the carrier member comprises a degradable elastomer with programmed mechanical properties to match the tissue mechanical and healing requirements. In some embodiments, the carrier member comprises at least one of a bioactive or pharmacologically active agent (e.g., to facilitate tissue repair and function), an anti-inflammatory material, an anti-fibrotic material, an anti-thrombotic material, growth-enhancing or promoting material, and an anti-biotic material, within, released from, or on the carrier member. At least part of the carrier member may be hydrophilic, wettable by water and body fluids. In some embodiments, at least part of the carrier member may be hydrophilic, wetting, and lubricious. In some embodiments, at least part of the carrier member comprises a swellable material. The swellable material may comprise a hydrogel of either synthetic or biopolymer chemistry. In some embodiments, the swellable material comprises a polymer hydrogel. In some embodiments, the carrier member comprises a sheet. In some embodiments, the sheet may be flexible. In some embodiments, the carrier member is substantially flat.

In some embodiments, at least one of the carrier member, the one or more first attachment members, and the one or more second attachment members comprise biodegradable material. The biodegradable material may comprise at least one of biodegradable polyester, polyanhydride, polytyrosine, fibrin glue, and polyamide. In some embodiments, at least one of the carrier member, the one or more first attachment members, and the one or more second attachment members comprises a shape memory material that can be degradable or non-degradable by design. The biodegradable polyester may comprise at least one of polycaprolactone, poly(L-lactide), poly(D,L-lactide), and poly(glycolide-co-lactide). The molecular weight of the polycaprolactone may be between about 150,000 and 250,000 and the molecular weight of the poly(L-lactide), poly(D,L-lactide), or poly(glycolide-co-lactide) may be between about 150,000 and 250,000. In some embodiments, the molecular weight of the polycaprolactone may be less than about 150,000 and the molecular weight of the poly(L-lactide), poly(D,L-lactide), or poly(glycolide-co-lactide) may be less than about 150,000. In some embodiments, the molecular weight of the polycaprolactone may be greater than about 250,000 and the molecular weight of the poly(L-lactide), poly(D,L-lactide), or poly(glycolide-co-lactide) may be greater than about 250,000. In some embodiments, at least one of the one or more first attachment members and the one or more second attachment members is configured to transform from a non-engaging configuration to an engaging configuration upon application of a stimulus. In some embodiments, the stimulus comprises at least one of light, heat, and moisture (e.g., aqueous moisture). In some embodiments, the stimulus comprises at least one of light, heat, and organic solvents.

In some embodiments, at least one of (a) the carrier member and (b) at least one of the first attachment members comprises a pharmacology active connective tissue growth promoter or factor. In some embodiments, at least one of (a) the carrier member and (b) at least one of the first attachment members comprises a bioactive connective tissue growth factor. At least part of the carrier member may be permeable or porous. In certain embodiments, at least part of the carrier member comprises a lattice design. At least one of the one or more first attachment members and the one or more second attachment members may protrude from an intersection point of the lattice design. In certain embodiments, the carrier member is flexible such that the carrier member can conform to the connective tissue.

In some embodiments, the carrier member is configured to conform into a cylindrical structure such that a first opening is formed at the first part, a second opening is formed at the second part, and the junction is disposed between the first opening and the second opening. In certain embodiments, a first rim is formed at the first opening and a second rim is formed at the second opening. The one or more first attachment members may protrude from the first rim in an interior of the cylindrical structure and the one or more second attachment members may protrude from the second rim in the interior of the cylindrical structure. In some embodiments, the first portion comprises at least one of a ligament and a tendon. In some embodiments, the first portion and the second portion are of the same connective tissue type.

According to various embodiments of the subject disclosure, a method for fixating connective tissue is provided. The method may comprise affixing a fixation device to a first portion of connective tissue and a second portion of connective tissue. The fixation device comprises a carrier member having a first part, a second part, and a junction therebetween. The carrier member may be configured to encompass, at least in part, an interior space. The fixation device further comprises one or more first attachment members protruding into the interior space and at a first angle from the first part toward the junction. The one or more first attachment members may be configured to engage the first portion in the interior space for attaching the first part to the first portion. The fixation device further comprises one or more second attachment members protruding from the second part into the interior space. The one or more second attachment members may be configured to engage the second portion in the interior space for attaching the second part to the second portion. The fixation device is affixed to the first portion and the second portion such that (a) the first part conforms to the first portion and the one or more first attachment members engage the first portion, (b) the second part conforms to the second portion and the one or more second attachment members engage the second portion, and (c) the junction is disposed approximately between the first portion and the second portion. When the first part is attached to the first portion and the second part is attached to the second portion, the first portion and the second portion are held reliably within the fixation device and limited in being pulled apart from one another during physiological use of the connective tissue.

In some embodiments, the carrier member has a length, width, and thickness. The length and width may each be at least two times, three times, four times, five times, eight times, ten times, 15 times, 20 times, 25 times, 50 times, 100 times, or 200 times greater than the thickness.

In some embodiments, the method further comprises coupling the first portion to the second portion. The coupling may comprise attaching the first portion to the second portion with at least one of a suture, staple, pin, tack, surgical adhesive or glue, and thermal bond. In some embodiments, the affixing further comprises transforming at least one of the one or more first attachment members and the one or more second attachment members from a non-engaging configuration to an engaging configuration. In some embodiments, the transforming comprises applying a stimulus to at least one of the one or more first attachment members and the one or more second attachment members. The stimulus may comprise at least one of light, heat and, moisture (e.g., aqueous moisture). In some embodiments, the stimulus may comprise at least one of light, heat, and organic solvents.

According to various embodiments of the subject disclosure, a method for fixating connective tissue is provided. The method comprises providing a fixation device comprising a carrier member having a first part, a second part, and a junction therebetween. The fixation device further comprises one or more first attachment members protruding at a first angle from the first part toward the junction. The one or more first attachment members may be configured to engage a first portion of connective tissue for attaching the first part to the first portion. The fixation device further comprises one or more second attachment members protruding from the second part. The one or more second attachment members may be configured to engage a second portion of connective tissue for attaching the second part to the second portion. The carrier member is configured to conform into a cylindrical structure such that a first opening is formed at the first part, a second opening is formed at the second part, the junction is disposed between the first opening and the second opening, the one or more first attachment members protrude from the first part in an interior of the cylindrical structure, and the one or more second attachment members protrude from the second part in the interior of the cylindrical structure.

The method also comprises advancing, when the carrier member is conformed into the cylindrical structure, the first portion through the first opening into the interior of the cylindrical structure until a tip of the first portion reaches the junction such that the one or more first attachment members engage the first portion. The method also comprises advancing, when the carrier member is conformed into the cylindrical structure, the second portion through the second opening into the interior of the cylindrical structure until a tip of the second portion reaches the junction such that the one or more second attachment members engage the second portion. When the first part is attached to the first portion and the second part is attached to the second portion, the first portion and the second portion are limited in being pulled apart from one another during physiological use of the connective tissue.

In some embodiments, the method may further comprise conforming the carrier member into the cylindrical structure. In some embodiments, the advancing the first portion comprises coupling the tip of the first portion to a first suture and advancing the first suture through the first opening into the interior of the cylindrical structure such that the first portion is drawn into the interior of the cylindrical structure through the first opening. In some embodiments, the advancing the second portion comprises coupling the tip of the second portion to a second suture and advancing the second suture through the second opening into the interior of the cylindrical structure such that the second portion is drawn into the interior of the cylindrical structure through the second opening. In some embodiments, the method further comprises transforming at least one of the one or more first attachment members and the one or more second attachment members from a non-engaging configuration to an engaging configuration. In some embodiments, the transforming comprises applying a stimulus to at least one of the one or more first attachment members and the one or more second attachment members. The stimulus may comprise at least one of light, heat, and moisture (e.g., aqueous moisture). In some embodiments, the stimulus may comprise at least one of light, heat, and organic solvents.

Additional features and advantages of the invention will be set forth in the description below, and in part will be apparent from the description, or may be learned by practice of the invention. The advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The accompanying drawings, which are included to provide further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate aspects of the invention and together with the description serve to explain the principles of the invention.

FIG. 1 illustrates an example of a fixation device for fixating connective tissue, in accordance with various embodiments of the subject disclosure.

FIG. 2A illustrates a side view of an attachment member and FIG. 2B illustrates a front view of the attachment member, in accordance with various embodiments of the subject disclosure.

FIGS. 3A, 3B, and 3C illustrate examples of an attachment member, in accordance with various embodiments of the subject disclosure.

FIGS. 4A and 4B illustrate arrangements of the attachment members, in accordance with various embodiments of the subject disclosure.

FIGS. 5A and 5B illustrate the flexibility of the fixation device, in accordance with various embodiments of the subject disclosure.

FIGS. 6A, 6B, 6C, 6D, 6E, 6F, 6G, and 6H illustrate examples of various configurations of the flexible device, in accordance with various embodiments of the subject disclosure.

FIG. 7 illustrates an example of a method for fixating connective tissue, in accordance with various embodiments of the subject disclosure.

FIGS. 8A, 8B, 8C, and 8D illustrate an example of a method for fixating connective tissue, in accordance with various embodiments of the subject disclosure.

FIG. 9 illustrates an example of a method for fixating connective tissue, in accordance with various embodiments of the subject disclosure.

FIGS. 10A, 10B, 10C, and 10D illustrate an example of a method for fixating connective tissue, in accordance with various embodiments of the subject disclosure.

FIGS. 11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, and 11I illustrate examples of the fixation device, in accordance with various embodiments of the subject disclosure.

FIGS. 12A and 12B of examples of experiments conducted with the fixation device, in accordance with various embodiments of the subject disclosure.

FIG. 13 illustrates an example of manufacturing the fixation device, in accordance with various embodiments of the subject disclosure.

DETAILED DESCRIPTION OF THE INVENTION

In the following detailed description, numerous specific details are set forth to provide a full understanding of the present invention. It will be apparent, however, to one ordinarily skilled in the art that the present invention may be practiced without some of these specific details. In other instances, well-known structures and techniques have not been shown in detail so as not to obscure the present invention.

Immediate causes of repair failure may be attributed to failure at the tendon-suture interface. A significant limitation of suture repair is that the strength of repair may be dependent on the ability of the tendon to hold the suture. The few points at which the suture is anchored in the tendon may result in points of high stress during tensile loading, leading to shredding at the tendon-suture interface as the suture begins cutting down the tendon. Macroscopically, this is observed by the occurrence of gapping between the mended tendon ends as the anchor points in the tendon are compromised. Furthermore, trumpeting at the repair site may cause fusiform swelling in the tendon at the repair site, which may inhibit gliding. Additionally, lack of motion after repair to protect the repair may cause adhesion to the tendon sheath.

Various approaches for the improvement of tendon repair include using stronger suture materials, strengthening the tissue at the tendon-suture interface, and tissue engineering approaches in conjunction with a suture-repair. However, these approaches fail to address the issue where repair with suture may create high stress points at the few anchor points of the suture in the tendon, leading to the complications that can result in repair failure. Along with biomechanical complications associated with suture repair, the quality of the repair itself may be highly dependent on surgeon experience and skill level. The complexities of the suture techniques are technically demanding, and variations between repair quality and overall surgery length can lead to deviations between patient outcomes.

According to certain embodiments of the subject disclosure, a significant contribution to the advancement of orthopedic technologies is provided to facilitate tissue fixation, stabilization and healing, and hence, repair and restoration of function. A problem associated with suture-repair occurs when tensile loads are concentrated to a few anchor points, which may result in failure at the tendon-suture interface and ultimately repair failure. In certain embodiments, this problem associated with suture-repair is addressed. In certain embodiments, by providing a device-based approach to tendon repair, variability and quality of repair due to surgeon experience can be reduced or eliminated because of a standardized approach. In some embodiments, a device, for example with a sheath design, is provided that may limit trumpeting by investing the tendon ends. The device may also address adhesion formation by acting as a physical barrier to adhesion formation, with an outer surface coated with suitable materials to prevent adhesion. In addition to tendons, the subject technology may be applied to ligaments and other suitable tissue known to those of ordinary skill in the art.

FIG. 1 illustrates an example of a fixation device 10 for fixating connective tissue, in accordance with various embodiments of the subject disclosure. Fixation device 10 comprises a carrier member 12 having a first part 14 a, a second part 14 b, and a junction 16 therebetween. The carrier member 12 may be configured to encompass, at least in part, an interior space. For example, one side of the carrier member 12 may be wrapped to another side of the carrier member 12 to encompass, at least in part, the interior space. However, the two sides of the carrier member 12 do not necessarily have to be coupled to one another to encompass the interior space. The junction 16 can be a line, zone, or region. Fixation device 10 also comprises one or more first attachment members 18 a protruding into the interior space and at a first angle from the first part 14 a toward the junction 16. The one or more first attachment members 18 a are configured to engage a first portion of connective tissue of a mammal in the interior space for attaching the first part 14 a to the first portion of connective tissue. Fixation device 10 also comprises one or more second attachment members protruding from the second part into the interior space, the one or more second attachment members 18 b configured to engage a second portion of connective tissue in the interior space for attaching the second part 14 b to the second portion of connective tissue. When the first part 14 a is attached to the first portion of connective tissue and the second part 14 b is attached to the second portion of connective tissue, the first portion of connective tissue and the second portion of connective tissue are limited in being pulled apart from one another during physiological use of the connective tissue. In some embodiments, physiological use means ordinary or typical use of connective tissue in its ordinary function. For example, physiological use of ligaments and tendons in the foot, ankle, or leg may include walking, running, and jumping.

In some embodiments, carrier member 12 may have a tissue-facing surface 22, upon which the attachment members 18 (e.g., attachment members 18 a and 18 b) protrude from. Carrier member 12 may also have an opposing surface 20 that is opposite the side of the tissue-facing surface 22. For example, the opposing surface 20 may be a surface that faces away from the connective tissue that the fixation device 10 is affixed to. The attachment members 18 may be oriented such that they protrude towards the junction 16 and are substantially aligned with a longitudinal dimension 24 of the carrier member 12. In some embodiments, the one or more second attachment members 18 b protrude at a second angle from the second part 14 b toward the junction 16. In some embodiments, the carrier member 12 comprises a sheet. In some embodiments, sheet, as used herein, may be given its broadest reasonable meaning. In some embodiments, a sheet may be substantially broad, flexible, and flat. In some embodiments, the carrier member 12 comprising a sheet may refer to the carrier member 12 having a length 46, width 48 and thickness 50, where the length 46 and width 48 each are at least two times, three times, four times, five times, eight times, ten times, 15 times, 20 times, 25 times, 50 times, 100 times, or 200 times greater than the thickness 50. In some embodiments, the carrier member 12 is substantially flat. In some embodiments, the carrier member 12 is integral with the attachment members 18. In some embodiments, the longitudinal dimension 24 of the carrier member 12 may be the direction connecting the first part 14 a and the second part 14 b (e.g., a direction substantially perpendicular to the junction and substantially in the plane of the carrier member 12).

In some embodiments, fixation device 10 may comprise biomaterial and can be formed either prior to or upon tissue placement into a tissue joining cuff that exerts holding forces on connective tissue, comparable to a suture repair, without the destructive effects mentioned previously. In some embodiments, the attachment members 18 can be rigid and produce a porcupine-quill (or alligator teeth) mimetic securing effect by resisting tissue pull-out. The attachment members 18 may spread the tensile loading forces among many points, so as not to overload the connective tissue at any single anchor point, reducing tissue trauma and increasing immobilizing forces within the fixation device 10. Furthermore, the orientation of the attachment members 18 a and the attachment members 18 b allow for easy insertion of connective tissue into the cuff one way, but restrict removal or movement in the opposite direction, similar to how a finger can slide into a Chinese finger-trap but not pull out. When the fixation device 10 is attached to portions of connective tissue, the portions of connective tissue are limited in being pulled apart from one another for facilitating repair and re-union of the connective tissue within fixation device 10.

FIG. 2A illustrates a side view of an attachment member 18 and FIG. 2B illustrates a front view of the attachment member 18, in accordance with various embodiments of the subject disclosure. The attachment member 18 and the carrier member 12 meet at a base 36. The attachment member 18 comprises a body 26, a tip 34, and a base center 38. In some embodiments, the body 26 may be the portion of the attachment member 18 that protrudes from the carrier member 12. As shown in FIG. 2A, an attachment member 18 may protrude from the carrier member 12 at an angle 26. In some embodiments, the angle 26 is measured according to techniques known to those of ordinary skill in the art. In some embodiments, the angle 26 is measured between the tissue-facing surface 22 of the carrier member 12 and a line connecting the tip 34 and the base center 38. In some embodiments, angle 26 is less than or equal to about 5 degrees, 10 degrees, 15 degrees, 20 degrees, 30 degrees, 40 degrees, 45 degrees, 50 degrees, 65 degrees, 75 degrees, or 85 degrees. In some embodiments, the angle 26 of an attachment member 18 a protruding from part 14 a may be of the same magnitude as the angle 26 of an attachment member 18 b protruding from part 14 b.

According to certain embodiments, the average thickness 28 of an attachment member 18 may be measured along a direction substantially parallel to a longitudinal dimension 24 of the carrier member 12. In some embodiments, the average thickness 28 of an attachment member 18 is such that when a part 14 of carrier member 12 is attached to a portion of connective tissue, angle 26 is maintained at less than about 5 degrees, 10 degrees, 15 degrees, 20 degrees, 30 degrees, 40 degrees, 45 degrees, 50 degrees, 65 degrees, 75 degrees, 85 degrees, or 90 degrees during physiological use of the connective tissue.

In some embodiments, a height 32 of an attachment member 18 is measured from the carrier member 12 to the farthest most extent that the attachment member 18 protrudes from the carrier member 12 (e.g., at the tip 34). In some embodiments, the average height of an attachment member 18 is greater than about 6 millimeters, between about 6 and 4 millimeters, between about 4 millimeters and 2 millimeters, between about 2 millimeters and 1.75 millimeters, between about 1.75 millimeters and 1.50 millimeters, between about 1.50 millimeters and about 1.25 millimeters, between about 1.25 millimeters and about 1 millimeter, between about 1 millimeter and about 0.75 millimeter, between about 0.75 millimeter and about 0.5 millimeter, between about 0.5 millimeter and about 0.25 millimeter, between about 0.25 millimeter and about 0.10 millimeter, between about 0.10 millimeter and about 0.075 millimeter, between about 0.075 millimeter and about 0.05 millimeter, between about 0.05 millimeter and about 0.025 millimeter, between about 0.025 millimeter and about 0.01 millimeter, or less than about 0.01 millimeter.

In some embodiments, the greatest width 30 of a base 36 of an attachment member 18 is measured along a direction substantially perpendicular to a longitudinal dimension of the base 36 and substantially parallel to the tissue-facing surface 22, the longitudinal dimension of the base 36 being a direction the attachment member 18 is protruding toward in substantially the same plane as the base 36. In some embodiments, the longitudinal dimension of the base 36 is the same as the longitudinal dimension 24 of carrier member 12. In some embodiments, a ratio of a greatest width 30 of a base 36 of an attachment member 18 to an average height of the attachment member 18 is greater than or equal to about 1.4, between about 1.4 and 1.2, between about 1.2 and 1.0, between about 1.0 and 0.95, between about 0.95 and about 0.90, between about 0.90 and about 0.80, between about 0.80 and about 0.70, between about 0.70 and about 0.60, between about 0.60 and about 0.50, between about 0.50 and about 0.40, between about 0.40 and about 0.30, between about 0.30 and about 0.20, between about 0.20 and about 0.10, or less than or equal to about 0.05.

According to various embodiments, the attachment member 18 is configured such that at least about 25%, 50%, 75%, or 95% of the body 26 of the attachment member 18 penetrates a portion of intended connective tissue when a part 14 of the carrier member 12 is attached to the portion of connective tissue. In some embodiments, the attachment member 18 is configured to penetrate the portion of intended connective tissue at a depth of less than about 0.01 millimeter, between about 0.01 millimeter and about 0.025 millimeter, between about 0.025 millimeter and about 0.05 millimeter, between about 0.05 millimeter and about 0.075 millimeter, between about 0.075 millimeter and about 0.10 millimeter, between about 0.10 millimeter and about 0.25 millimeter, between about 0.25 millimeter and about 0.50 millimeter, between about 0.50 millimeter and about 0.75 millimeter, between about 0.75 millimeter and about 1 millimeter, between about 1 millimeter and about 1.25 millimeters, between about 1.25 millimeters and about 1.50 millimeters, between about 1.50 millimeters and about 1.75 millimeters, between about 1.75 millimeters and about 2 millimeters, between about 2 millimeters and about 3 millimeters, between about 3 millimeters and about 4 millimeters, between about 4 millimeters and about 6 millimeters, or greater than about 6 millimeters. The amount of penetration may depend on the force applied to the attachment member 18, the density of the intended connective tissue, the hardness of the connective tissue and/or the attachment member 18, or other suitable factors known to those of ordinary skill in the art.

A plurality of attachment members 18 may protrude from a part 14 of a carrier member 12. The part 14 may comprise a tissue-facing surface 22 that faces the connective tissue when the part 14 engages a first portion of the connective tissue. A fixation device 10 may comprise a number of different densities of attachment members 18 on the part 14. For example, the part 14 and each of the plurality of the attachment members 18 may meet at a respective base 36 having an area. A ratio of the total area of all the bases 36 to the total area of the tissue-facing surface 22 of the part 14 may be greater than or equal to about 0.05, 0.10, 0.20, 0.30, 0.40, 0.50, 0.60, 0.70, 0.80, 0.90, or 0.95. In some embodiments, a high ratio is desirable. In some embodiments, by having a large number of attachment members 18 disposed on a carrier member 12, the resulting surface disperses load over a larger surface area as opposed to a carrier member 12 with fewer attachment members 18.

FIGS. 3A, 3B, and 3C illustrate examples of an attachment member 18, in accordance with various embodiments of the subject disclosure. An attachment member 18 may have a different shape or angle with respect to other attachment members 18 protruding from the same carrier member 12. In some embodiments, all the attachment members 18 protruding from a part 14 of a carrier member 12 may be oriented in the same direction. In some embodiments, an attachment member 18 may comprise at least one of a hook, a barb, and a pin.

In some embodiments, a method for creating oriented, spaced attachment members 18 in carrier member 12 uses an oriented direct fiber transfer process to embed oriented fibers of attachment members 18 into carrier member 12 by either electrostatic forces or mechanical alignment to yield the final device.

In some embodiments, an electrostatic process utilizes a field of static electricity to orient the fibers of attachment members 18 relative to the applied electrostatic field and promote a perpendicular alignment of the fibers with respect to carrier member 12. For example, uncured carrier member 12 resin in a mold can be passed between the potentials of a high voltage electrostatic field. A local electrode may be utilized to give the fiber an electrostatic charge. The charged fibers may become aligned with the electrical field lines of force. The carrier member 12 resin and/or the grounded parts of the application machine may form a ground potential. The fibers of attachment members 18 may therefore be electrostatically attracted toward the carrier member 12 in the mold in the presence of the field, where they become embedded in the uncured liquid resin of carrier member 12 in its mold prior to curing. With this process, most fibers may be embedded within the carrier member 12 resin surface, adhering to the resin and may be oriented relative to carrier member 12 dictated by the orientation of the electrostatic field and electrodes placing the fibers relative to the plane of carrier member 12.

In some embodiments, the attachment members 18 may be non-conductive or uncharged, and the attachment members 18, as short fibers, may be transported and aligned predominately perpendicular to the release sheet through mechanical means, such as a sieving screening or alignment mask through which the attachment members 18 may fall through the openings to align and orient at fixed positions and at defined spacings in the resin prior to thermal or photo-curing.

In some embodiments, attachment members 18 embedded into carrier member 12 can include natural or synthetic fibers such as rayon, and other types of conductive materials including nylon, polyamide, polyester and similar synthetic fibers. The attachment members 18 can also include pre-formed ceramic or metal fibers, or related large aspect ratio needles, of millimeter length dimensions. In some embodiments, all of the attachment members 18 may be embedded into the carrier member 12 at a defined spacing and angular orientation relative to the plane of carrier member 12, and subsequently cured in place by thermal or photonic means securely to prevent release under stress or strain.

FIGS. 4A and 4B illustrate arrangements of the attachment members 18, in accordance with various embodiments of the subject disclosure. In some embodiments, attachment members 18 protruding from a carrier member 12 may be arranged in various configurations or in random configurations. As shown in FIG. 4A, the attachment members 18 are arranged with respect to the carrier member 12 in a staggered array. As shown in FIG. 4B, the attachment members 18 are arranged with respect to the carrier member 12 in a grid-like array. The attachment members 18 may be arranged with respect to the carrier member 12 in at least one of the grid-like array and the staggered array.

FIGS. 5A and 5B illustrate the flexibility of the fixation device 10, in accordance with various embodiments of the subject disclosure. In some embodiments, the fixation device 10 is elastic. For example, FIGS. 5A and 5B illustrate that the fixation device 10 can be stretched in its longitudinal direction. In some embodiments, the carrier member 12 may be flexible such that the carrier member 12 can readily conform to the connective tissue. In some embodiments, an attachment member 18 protruding from the carrier member 12 is less elastic than is the carrier member 12. In some embodiments, the carrier member 12 allows deployment of the attachment members 18 into a fully extended and exposed position for optimal tissue engagement by stretching the carrier member 12.

FIGS. 6A, 6B, 6C, 6D, 6E, 6F, 6G, and 6H illustrate examples of various configurations of the flexible device 10, in accordance with various embodiments of the subject disclosure. As shown in FIG. 6A, the fixation device 10 may be conformed about its longitudinal dimension 24 into a cylindrical structure such that the attachment members 18 are in an interior of the fixation device 10. Thus, the opposing surface 20 is on an exterior of the fixation device 10. This configuration may be used, for example, to wrap the fixation device 10 around portions of connective tissue. As shown in FIG. 6B, the fixation device 10 may be conformed about its longitudinal dimension 24 into a cylindrical structure such that the attachment members 18 are in an exterior of the fixation device 10. Thus, the opposing surface 20 is in an interior of the fixation device 10. This configuration may be used, for example, to place the fixation device 10 within various organs and tissue as a stent-like device. In some embodiments, the fixation device 10 may be used as a tape-like or bandage-like device and placed over tears or rips in tissue or organs to facilitate repair. In some embodiments, two fixation devices 10 may be placed on opposite sides of a tissue site to be fixed. The attachment members 18 from each face of the two fixation devices 10 may be engaged into opposite faces of the tissue to be fixed, and the edges of two fixation devices 10 may be secured to each other around the tissue site to hold the tissue within a sandwich structure between the two fixation devices 10.

In some embodiments, at least one of the carrier member 12 and the attachment members 18 may comprise a shape memory material. In this case, the fixation device 10 may spontaneously conform to a shape of the connective tissue upon application of a stimulus (e.g., light (ultraviolet or other forms), heat, moisture (e.g., aqueous moisture), and/or other suitable stimuli). In some embodiments, the stimulus may comprise at least one of light, heat, and organic solvents. For example, the fixation device 10 may deploy and roll up around connective tissue to engage the connective tissue upon application of the stimulus. In some embodiments, the fixation device 10 may be in a flat configuration when engaging the connective tissue. The fixation device 10 may then conform to the connective tissue (e.g., wrap around the connective tissue) upon application of the stimulus. In some embodiments, the attachment members 18 may be deployed based on the shape memory material. In some embodiments, the attachment members 18 may be configured to transform from a non-engaging configuration to an engaging configuration upon application of a stimulus. For example, when the stimulus has not been applied, the attachment members 18 may be in a non-engaging configuration such as being hidden, lying flat against the tissue facing surface 22, being sufficiently soft, or otherwise being in a configuration in which the attachment members 18 do not engage or minimally engage connective tissue when the fixation device 10 engages the connective tissue. Upon application of the stimulus, the attachment members 18 may transform into an engaging configuration such as becoming exposed, protruding at a suitable angle from the tissue facing surface 22, becoming sufficiently rigid, or otherwise transforming into a configuration in which the attachment members 18 may sufficiently engage connective tissue when the fixation device 10 engages the connective tissue. In one example, the attachment members 18 may be hidden when dry, but may be exposed and become rigid when wet to engage the connective tissue.

According to certain embodiments, at least part of the carrier member 12 of fixation device 10 may comprise a lattice design. As shown in FIGS. 6C and 6D, fixation device 10, which is conformed in a cylindrical structure, may be loaded onto a mandrel 52. Using laser cutting or other suitable techniques known to those of ordinary skill in the art, a lattice design 54 may be created on the carrier member 12 of fixation device 10, as shown in FIGS. 6D and 6E. Such a configuration beneficially allows for diffusion to and from the connective tissue through the holes of the lattice design 54 when the fixation device 10 is engaged to the connective tissue. In some embodiments, such a configuration may also allow fixation device 10 to be of sufficient elasticity, for example, to stretch and wrap around connective tissue. In some embodiments, the attachment members 18 may protrude from the one or more intersection points 56 of the lattice design 54. However, the attachment members 18 may protrude anywhere from the carrier member 12, including along the sides of the criss-cross pattern of the lattice design 54.

According to certain embodiments, other techniques may be used to provide a fixation device 10 having holes on the carrier member 12 to facilitate diffusion to and from the connective tissue when the fixation device 10 is engaged to the connective tissue. For example, as shown in FIG. 6F, strips of fiber may be weaved together to form a meshwork design for carrier member 12 of the fixation device 10. In another example, as shown in FIG. 6G, strips of fiber may be knitted together to form a meshwork design for the carrier member 12 of the fixation device 10. In some embodiments, biosensor drilling may be used to drill holes into the carrier member 12. FIG. 6H illustrates an example of the fixation device 10 conformed in a cylindrical structure and utilizing a meshwork design. The attachment members 18 may protrude from an interior of rims 58 a and 58 b formed at the respective openings of the cylindrical structure. However, the attachment members 18 may also protrude from other areas of the fixation device 10, including an exterior of rims 58 a and 58 b and/or along the fibers of the meshwork design.

FIGS. 7, 8A, 8B, 8C, and 8D illustrate an example of a method 700 for fixating a first portion 40 a of connective tissue to a second portion 40 b of connective tissue, in accordance with various embodiments of the subject disclosure. Method 700 comprises affixing the fixation device 10 (e.g., as shown in FIGS. 1 and 6A) to the first portion 40 a and the second portion 40 b, as shown in FIGS. 8C and 8D. In some embodiments, the fixation device 10 is affixed to the first portion 40 a and the second portion 40 b such that (a) the first part 14 a conforms to the first portion 40 a and the one or more first attachment members 18 a engage the first portion 40 a, (b) the second part 14 b conforms to the second portion 40 b and the one or more second attachment members 18 b engage the second portion 40 b, and (c) the junction 16 is disposed approximately between the first portion 40 a and the second portion 40 b. In some embodiments, method 700 also comprises coupling the first portion 40 a of connective tissue to the second portion 40 b of connective tissue, for example, as shown in FIG. 8B with an elongate member 42. The elongate member 42 may comprise suture used to tie the first portion 40 a together with the second portion 40 b. The coupling may comprise other means to couple the first portion 40 a to the second portion 40 b. For example, the coupling may comprise attaching the first portion 40 a to the second portion 40 b with at least one of a suture, staple, pin, tack, surgical adhesive or glue, thermal bond, or other suitable methods known to those of ordinary skill in the art.

In some embodiments, fixation device 10 may be stretched along its longitudinal dimension 24 before being attached to the connective tissue such that when the first part 14 a attaches to the first portion 40 a and when the second part 14 b attaches to the second portion 40 b, the elasticity of the fixation device 10 causes the first part 14 a attached to the first portion 40 a and the second part 14 b attached to the second portion 40 b to be flexed back towards one another. The orientation of the one or more first attachment members 18 a and the one or more second attachment members 18 b may prevent the first portion 40 a from being pulled apart from the second portion 40 b and vice versa. In some embodiments, when the first part 14 a is attached to the first portion 40 a and the second part 14 b is attached to the second portion 40 b, the first portion 40 a and the second portion 40 b are limited in being pulled apart from one another during physiological use of the connective tissue.

In some embodiments, the first portion 40 a comprises at least one of a ligament and a tendon. In some embodiments the second portion 40 b comprises at least one of a ligament and a tendon. In some embodiments, the first portion 40 a and the second portion 40 b are of the same connective tissue type.

FIGS. 9, 10A, 10B, 10C, and 10D illustrate an example of a method 900 for fixating a first portion 40 a of connective tissue to a second portion 40 b of connective tissue, in accordance with various embodiments of the subject disclosure. Method 900 comprises providing a fixation device 10 comprising a carrier member 12 having a first part 14 a, a second part 14 b, and a junction 16 therebetween (e.g., as shown in FIGS. 1 and 6A). The carrier member 12 is configured to conform into a cylindrical structure (e.g., as shown in FIGS. 6A, 10B, 10C, and 10D) such that a first opening 44 a is formed at the first part 14 a, a second opening 44 b is formed at the second part 14 b, the junction 16 is disposed between the first opening 44 a and the second opening 44 b, the one or more first attachment members 18 a protrude from the first part 14 a in an interior of the cylindrical structure, and the one or more second attachment members 18 b protrude from the second part 14 b in the interior of the cylindrical structure. In some embodiments, method 900 comprises conforming the carrier member 12 into the cylindrical structure.

Method 900 also comprises advancing, when the carrier member 12 is conformed into the cylindrical structure, the first portion 40 a through the first opening 44 a into the interior of the cylindrical structure until a tip of the first portion 40 a reaches the junction 16 such that the one or more first attachment members 18 a engage the first portion 40 a. In some embodiments, the advancing the first portion 40 a comprises coupling the tip of the first portion 40 a to a first elongate member 42 a and advancing the first elongate member 42 a through the first opening 44 a into the interior of the cylindrical structure such that the first portion 40 a is drawn into the interior of the cylindrical structure through the first opening 44 a (e.g., as shown in FIGS. 10B and 10C). The first elongate member 42 a may comprise suture, thread, or any other suitable mechanism known to those of ordinary skill in the art useful for pulling the first portion 40 a.

Method 900 also comprises advancing, when the carrier member 12 is conformed into the cylindrical structure, the second portion 40 b through the second opening 44 b into the interior of the cylindrical structure until a tip of the second portion 40 b reaches the junction 16 such that the one or more second attachment members 18 b engage the second portion 40 b. In some embodiments, the advancing the second portion 40 b comprises coupling the tip of the second portion 40 b to a second elongate member 42 b and advancing the second elongate member 42 b through the second opening 44 into the interior of the cylindrical structure such that the second portion 42 b is drawn into the interior of the cylindrical structure through the second opening 44 b. The second elongate member 42 b may comprise suture, thread, or any other suitable mechanism known to those of ordinary skill in the art useful for pulling the second portion 40 b. In some embodiments, when the first part 14 a is attached to the first portion 40 a and the second part 14 b is attached to the second portion 40 b, the first portion 40 a and the second portion 40 b are limited in being pulled apart from one another during physiological use of the connective tissue.

According to various embodiments of the subject disclosure, the fixation device 10 as discussed herein may be applied for use in other applications involving tissue repair. For example, in addition to use with tendons and ligaments, the fixation device 10 may be applied to the organs of the gastrointestinal system or urinary system of a mammal. These organs may include, but not limited to, the esophagus, stomach, small and large intestines, mouth, colon, anus, appendix, gallbladder, liver, pancreas, kidneys, urethers, bladder, urethra, or other suitable organs known to those of ordinary skill in the art. The fixation device 10 may be used as a cylindrical structure (e.g., as shown in either FIGS. 6A and 6B) in attaching to tissue or alternatively may be used as a tape-like, bandage-like, or sandwiching-like device to be patched onto organs where repair is needed. FIGS. 11A, 11B, 11C, 11D, 11E, 11F, 11G, 11H, and 11I illustrate examples of the fixation device 10, in accordance with various embodiments of the subject disclosure.

FIGS. 12A and 12B of examples of experiments conducted with the fixation device 10, in accordance with various embodiments of the subject disclosure. FIG. 12A illustrates an example of single-tendon uniaxial tensile testing to determine the holding strength of the fixation device 10 on a tendon. To test the holding strength, the force needed to pull the tendon out of the sleeve is determined by uniaxial tensile loading on an Instron at a displacement ramp rate of about 0.5 millimeters per second while recording displacement and force on the load cell. This test set-up involves wrapping the fixation device 10 around a bovine tendon to cover the area one inch up from the end of the tendon, with the attachment members 18 facing toward the end of the tendon. The fixation device 10 is taped circumferentially to prevent the device from opening up, and the two ends of a nylon strap are glued on opposite sides of the formed sleeve to form a loop. The free end of the tendon is placed into a freeze clamp, while the loop is secured to the testing bench via a bolt to hold the strap down. FIG. 12B illustrates a single tendon pull out force of the fixation device 10, in accordance with various embodiments of the subject disclosure. As shown in FIG. 12B, the strength of fixation of suture repair is at about 60 Newtons, with a failure of fixation defined as a gap of greater than 3 millimeters. In some embodiments, use of the fixation device 10 may allow for a force being applied at greater than about 60 Newtons.

FIG. 13 illustrates an example of manufacturing the fixation device 10, in accordance with various embodiments of the subject disclosure. As shown in FIG. 13, a computer numerical controlled (CNC) machine may be used to fabricate the fixation device 10. In some embodiments, the fixation device may be manufactured utilizing solventless fabrication techniques. To move into solvent-free production, photo-curable polymers may be used, as well as thermal-melt processing methods in place of the solvent casting techniques. This may be advantageous in a manufacturing perspective because there would be no organic waste to deal with and no additional time needed to extract residual solvent that may still be present in the materials of the fixation device 10. Because the fixation device 10 is implanted into the body of a mammal, it is important to eliminate concerns of toxicity due to possibility of residual chemicals from processing. In some embodiments, materials to be used in fabricating the fixation device 10 include materials already approved for implantation in the body by the United States Food and Drug Administration (FDA).

A CNC machine may be used to create a mold for fabricating the fixation device 10. The CNC machine tool may move a surgical blade in and out of the mold medium to create surface structures and indentations. A tilting platform on the CNC benchtop may allow its blade to enter the mold at various angles. The size of each attachment member 18 may be controlled by the depth the blade enters the mold. The angle 26 of each attachment member 18 may be controlled by the angle of the tilting platform. The number and placement of the attachment members 18 may be modified in the computer code that runs the program of the CNC machine. A computer operated laser-cutting machine may also produce precise analogous surface structures in the device using photon energy or ablation instead of mechanical cutting.

According to various embodiments of the subject disclosure, mold-making begins with melting paraffin wax into a petri dish, and covering it to let the wax cool slowly and evenly. In some embodiments, the tips of No. 11 surgical blades may be used to penetrate the wax at a desired depth (e.g., at about 2 millimeters) and at a desired angle (e.g., at about 20 degrees) from the surface, leaving negatives of what will become the attachment members 18. The casting polyurethane, for example, Alumilite, may be cast onto the wax mold and placed in a vacuum (e.g., at −22 mmHg) to ensure all the gas from the small negative spaces are evacuated out so as to produce a precise positive of the entire array of attachment members 18. Following curing and removal from the wax mold, the Alumilite positive may be placed in another petri dish, with the attachment members 18 side facing up, where a room temperature curing platinum silicone elastomer, for example VST-50 from Factor II, Inc., can be cast over the Alumilite and placed in vacuum to ensure complete fidelity to the Alumilite positive. After curing, the silicone elastomer can be peeled off the Alumilite and used as the final heat-resistant, reusable master mold.

In some embodiments, fabrication of the fixation device 10 may involve a two-part technique to create a bimodal, composite material with rigid attachment members 18 and the carrier member 12 (e.g., an elastomeric film). To create the attachment members 18 for the carrier member 12, a rigid material is cast into the mold to provide the strength needed to support resisting forces. In some embodiments, the attachment members 18 comprise a polymer. In some embodiments, the attachment members 18 comprise at least one of a thermoplastic (e.g., poly(methyl methacrylate) (PMMA), PMMA-copolymers, and Acrylotem-M from Ovation Polymers), ultraviolet curable resin (e.g., UV-Cure 7165 from Deco-Coat Products), biodegradable polyester (e.g., polycaprolactone from Sigma-Aldrich and poly(L-lactide) from Sigma-Aldrich), biomedical grade polycarbonate urethane (e.g., Bionate 75D from DSM Biomedical), shape memory polyesters and polyurethanes (e.g., from DSM Biomedical), and degradable polyurethane. These materials may be medical grade. The biodegradable polyester may comprise at least one of polycaprolactone, poly(L-lactide), poly(D,L-lactide), and poly(glycolide-co-lactide), wherein the molecular weight of the polycaprolactone is between about 150,000 and 250,000 and the molecular weight of the poly(L-lactide), poly(D,L-lactide), or poly(glycolide-co-lactide) is between about 150,000 and 250,000. In some embodiments, the molecular weight of the polycaprolactone may be less than about 150,000 and the molecular weight of the poly(L-lactide), poly(D,L-lactide), or poly(glycolide-co-lactide) may be less than about 150,000. In some embodiments, the molecular weight of the polycaprolactone may be greater than about 250,000 and the molecular weight of the poly(L-lactide), poly(D,L-lactide), or poly(glycolide-co-lactide) may be greater than about 250,000. In some embodiments, the attachment member 18 comprises non-polymeric resorbable biomaterials including calcium-based ceramics (e.g., calcium phosphates, various hydroxyapatites, carbonates or sulfates), biocompatible silicates (e.g., bioglasses), silicon or titanium nitrides or oxides, or their composites with degradable polymers (e.g., biomedical grade degradable or non-degradable polyester or polyurethane).

In some embodiments, the carrier member 12 comprises an elastomer, preferably a medical grade elastomer. In some embodiments, the carrier member 12 comprises a degradable medical grade elastomer. In some embodiments, the carrier member 12 comprises a shape memory degradable elastomer (e.g., segmented polyester urethane). In some embodiments, the carrier member 12 comprises a shape memory non-degrading elastomer. In some embodiments, the carrier member 12 comprises at least one of an ultraviolet curable resin (e.g., Acrylotem-P-Soft-85 from Ovation polymers), methacrylated polybutadiene (e.g., Ricacryl 3500 from Sartomer), and polyether urethane (e.g., Biospan Segmented Polyether Urethane from DSM Biomedical).

In some embodiments, for a thermal melt, the attachment members 18 may comprise at least one of polycarbonate urethane (e.g., Bionate 75D from DSM Biomedical), polycaprolactone, poly(L-lactide), poly(D,L-lactide), and poly(glycolide-co-lactide), wherein the molecular weight of the polycaprolactone is between about 150,000 and 250,000 and the molecular weight of the poly(L-lactide), poly(D,L-lactide), or poly(glycolide-co-lactide) is between about 150,000 and 250,000. In some embodiments, for a thermal melt, the carrier member 12 may comprise polyether urethane (e.g., Biospan Segmented Polyether Urethane from DSM Biomedical). For a thermal melt, the polymer pellets are placed over the silicone mold in a vacuum oven and heated to melting point under vacuum. As the polymer melts, the polymer may flow into the spaces in the mold as the atmospheric gas is evacuated out. While the polymer is still in a liquid phase, the excess can be removed (e.g., by using a drawing blade or straight-edge razor blade as a squeegee), leaving behind the polymer only in the attachment member 18 cavities where the polymer can solidify again.

In some embodiments, for an ultraviolet (UV) photocrosslinking cure, the attachment members 18 may comprise at least one of a thermoplastic (e.g., poly(methyl methacrylate) (PMMA), PMMA-copolymers, and Acrylotem-M from Ovation Polymers) and ultraviolet curable resin (e.g., UV-Cure 7165 from Deco-Coat Products) or photo-curable polymer resin. These materials may be medical grade. In some embodiments, for a UV cure, the carrier member 12 may comprise at least one of ultraviolet curable resin (e.g., Acrylotem-P-Soft-85 from Ovation Polymers) and methacrylated polybutadiene (e.g., Ricacryl 3500 from Sartomer) or photocurable polymer resin. To use a UV curable technique, the UV curable polymer or its solutions can be poured over the silicone molds and then placed in vacuum to remove ambient atmosphere and completely fill the small spaces in the mold. After vacuum, the excess will be removed (e.g., by using a drawing blade or straight-edge razor blade as a squeegee), and then the remaining polymer can be exposed UV light (wavelength .about.360-365 nm, 10 mW/cm2) for approximately 1 minute to cure the resin in situ. The bulk portion of the fixation device 10 may created by casting an elastomeric polymer directly over the attachment members 18 still within the mold and curing or cooling to ambient temperature.

Using a thermal melt process, the carrier polymer can be heated to melting point and then simply cast onto the mold over the attachment members 18. Similarly, a UV curable polymer solution can be cast over the attachment members 18 and then exposed to UV light to cure. After the elastomeric portion has cooled, the carrier member 12 can be pulled off the silicone mold with the attachment members 18 intact within the carrier film, and exposed and decorated on and across its surface. In some embodiments, fabrication based on the foregoing techniques may reduce manufacture time and enhance device dimensional precision and fidelity and resulting physical feature qualities without the need of solvent chemistry.

In some embodiments, the fixation device 10 may be loaded at various mass fractions (doses) with bioactive or pharmacologically active or included biodegradable materials that release bioactive molecules, such as drugs (e.g., antibiotics, anti-inflammatories, anti-thrombotics, anti-fibrotics) and growth factors known to promote tissue repair. For example, antibiotics may include ceftazidime, gentamicin, tobramycin, vancomycin, and/or other suitable antibiotics. Anti-thrombotics may include warfarin, heparins, and/or other suitable anti-thrombotics. The bioactive inclusions can be loaded directly into any carrier member 12 or attachment member 18 materials for controlled release to the tissue surface over time without degradable materials. They can also be included deliberately within biodegradable carrier member 12 or attachment member 18 materials, or in biodegradable matrices within such materials (for example as micro- or nano-encapsulated drugs). For example, at least one of the carrier member 12 and the attachment members 18 may comprise biodegradable materials capable of holding and then releasing drugs upon degradation. The biodegradable material may include biodegradable polyester or biodegradable polyurethanes. In some embodiments, the biodegradable polyester comprises at least one of polycaprolactone, poly(L-lactide), poly(D,L-lactide), and poly(glycolide-co-lactide), wherein the molecular weight of the polycaprolactone is between about 150,000 and 250,000 and the molecular weight of the poly(L-lactide), poly(D,L-lactide), or poly(glycolide-co-lactide) is between about 150,000 and 250,000. In some embodiments, the molecular weight of the polycaprolactone may be less than about 150,000 and the molecular weight of the poly(L-lactide), poly(D,L-lactide), or poly(glycolide-co-lactide) may be less than about 150,000. In some embodiments, the molecular weight of the polycaprolactone may be greater than about 250,000 and the molecular weight of the poly(L-lactide), poly(D,L-lactide), or poly(glycolide-co-lactide) may be greater than about 250,000. In some embodiments, at least one of (a) the carrier member 12 and (b) the attachment members 18 comprises a connective tissue growth factor. The connective tissue growth factor can be part of the CCN family (e.g., CCN2) or comprise other suitable pharmacologically active factors known to those of ordinary skill in the art. In some embodiments, when a part 14 is attached to a portion 40 of connective tissue and as the biodegradable material progressively biodegrades, the connective tissue growth factor may be progressively released for promoting repair of the portion 40 of connective tissue. In some embodiments, at least part of the carrier member 12 may be permeable (e.g., for facilitating molecule diffusion into and/or out of portions 40 of connective tissue).

In some embodiments, anti-adhesive, anti-fibrotic, anti-inflammatory, and/or hydrophilic lubricious materials may be incorporated on the opposing surface 20 of the fixation device to prevent non-desirable adhesion formations. For example, the carrier member 12 may comprise a surface (e.g., opposing surface 20 and/or tissue-facing surface 22) having at least one of an anti-inflammatory material (e.g., corticosteroid, other suitable steroids, or other suitable anti-fibrotic materials known to those of ordinary skill in the art), an anti-thrombotic material, and an anti-biotic material, within, released from or on the carrier member 12. In some embodiments, these bioactive materials or other suitable biomaterials (e.g., slippery, wettable lubricious coatings based on hydrophilic polymers) known to those of ordinary skill in the art may be used to reduce adhesion formations on the surface. In some embodiments, at least part of the carrier member 12 is hydrophilic, wetting and lubricious against tissue surfaces. In some embodiments, at least part of the carrier member 12 comprises a swellable material. The swellable material may comprise a hydrogel. In some embodiments, at least one of the carrier member 12 and the attachment member 18 comprises a shape memory material.

The foregoing description is provided to enable a person skilled in the art to practice the various configurations described herein. While the present invention has been particularly described with reference to the various figures and configurations, it should be understood that these are for illustration purposes only and should not be taken as limiting the scope of the invention.

There may be many other ways to implement the invention. Various functions and elements described herein may be partitioned differently from those shown without departing from the scope of the invention. Various modifications to these configurations will be readily apparent to those skilled in the art, and generic principles defined herein may be applied to other configurations. Thus, many changes and modifications may be made to the invention, by one having ordinary skill in the art, without departing from the scope of the invention.

It is understood that the specific order or hierarchy of steps in the processes disclosed is an illustration of exemplary approaches. Based upon design preferences, it is understood that the specific order or hierarchy of steps in the processes may be rearranged. Some of the steps may be performed simultaneously. The accompanying method claims present elements of the various steps in a sample order, and are not meant to be limited to the specific order or hierarchy presented.

A phrase such as an “aspect” does not imply that such aspect is essential to the subject technology or that such aspect applies to all configurations of the subject technology. A disclosure relating to an aspect may apply to all configurations, or one or more configurations. A phrase such as an aspect may refer to one or more aspects and vice versa. A phrase such as an “embodiment” does not imply that such embodiment is essential to the subject technology or that such embodiment applies to all configurations of the subject technology. A disclosure relating to an embodiment may apply to all embodiments, or one or more embodiments. A phrase such an embodiment may refer to one or more embodiments and vice versa.

Furthermore, to the extent that the term “include,” “have,” or the like is used in the description or the claims, such term is intended to be inclusive in a manner similar to the term “comprise” as “comprise” is interpreted when employed as a transitional word in a claim.

The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

A reference to an element in the singular is not intended to mean “one and only one” unless specifically stated, but rather “one or more.” The term “some” refers to one or more. All structural and functional equivalents to the elements of the various configurations described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and intended to be encompassed by the invention. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the above description. 

What is claimed is:
 1. An apparatus for fixating connective tissue, the apparatus comprising: a carrier member having a first part, a second part, and a junction therebetween, the carrier member having a length, width, and thickness, the length and width each being at least two times greater than the thickness, the carrier member configured to encompass an interior space; one or more first attachment members protruding into the interior space and at a first angle from the first part toward the junction, the one or more first attachment members configured to engage a first portion of connective tissue in the interior space for attaching the first part to the first portion; and one or more second attachment members protruding from the second part into the interior space, the one or more second attachment members configured to engage a second portion of connective tissue in the interior space for attaching the second part to the second portion; wherein, when the first part is attached to the first portion and the second part is attached to the second portion, the first portion and the second portion are limited in being pulled apart from one another during physiological use of the connective tissue.
 2. The apparatus of claim 1, wherein the one or more second attachment members protrude at a second angle from the second part toward the junction.
 3. The apparatus of claim 2, wherein the first angle and the second angle are of about the same magnitude.
 4. The apparatus of claim 1, wherein an average thickness of at least one of the one or more first attachment members is such that when the first part is attached to the first portion, the first angle is maintained at less than about 90 degrees during physiological use of the connective tissue, wherein the average thickness is measured along a direction substantially parallel to a longitudinal dimension of the carrier member.
 5. The apparatus of claim 1, wherein at least one of the one or more first attachment members is less elastic than is the carrier member.
 6. The apparatus of claim 1, wherein an average height of at least one of the one or more first attachment members is between about 4 millimeters and 2 millimeters.
 7. The apparatus of claim 1, wherein the first part comprises a tissue-facing surface that faces the connective tissue when the first part engages the first portion, wherein the first part and each of the one or more first attachment members meet at a respective base having an area, wherein a ratio of the total area of all the bases to the total area of the tissue-facing surface is greater than or equal to about 0.70.
 8. The apparatus of claim 1, wherein the first part comprises a tissue-facing surface that faces the connective tissue when the first part engages the first portion, wherein the first part and each of the one or more first attachment members meet at a respective base having an area, wherein a ratio of the total area of all the bases to the total area of the tissue-facing surface is greater than or equal to about 0.90.
 9. The apparatus of claim 1, wherein at least three of the one or more first attachment members are arranged with respect to the carrier member in at least one of a grid-like array and a staggered array.
 10. The apparatus of claim 1, wherein at least one of the one or more first attachment members comprise at least one of a thermoplastic, ultraviolet curable resin, biodegradable polyester, polycarbonate urethane, and polyurethane.
 11. The apparatus of claim 1, wherein the carrier member comprises at least one of an ultraviolet curable resin, methacrylated polybutadiene, polyester urethane, polycarbonate polyurethane, polyether urethane, silicone rubber, nitrile rubber, polyphosphazene, and acrylic copolymer.
 12. The apparatus of claim 1, wherein the carrier member comprises a sheet.
 13. The apparatus of claim 1, wherein at least part of the carrier member comprises a lattice design.
 14. The apparatus of claim 1, wherein at least one of the carrier member, the one or more first attachment members, and the one or more second attachment members comprises a shape memory material. 